EP0043338B1 - Feuerfeste, gasdurchlässige Baukörper - Google Patents

Feuerfeste, gasdurchlässige Baukörper Download PDF

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Publication number
EP0043338B1
EP0043338B1 EP81630044A EP81630044A EP0043338B1 EP 0043338 B1 EP0043338 B1 EP 0043338B1 EP 81630044 A EP81630044 A EP 81630044A EP 81630044 A EP81630044 A EP 81630044A EP 0043338 B1 EP0043338 B1 EP 0043338B1
Authority
EP
European Patent Office
Prior art keywords
metal
gas
structural unit
elements
segments
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP81630044A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0043338A1 (de
Inventor
Fritz Hödl
Friedrich Kassegger
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Arcelor Luxembourg SA
Original Assignee
Arbed SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from LU82554A external-priority patent/LU82554A1/de
Priority claimed from LU82553A external-priority patent/LU82553A1/de
Priority claimed from LU82552A external-priority patent/LU82552A1/de
Application filed by Arbed SA filed Critical Arbed SA
Priority to AT81630044T priority Critical patent/ATE15389T1/de
Publication of EP0043338A1 publication Critical patent/EP0043338A1/de
Application granted granted Critical
Publication of EP0043338B1 publication Critical patent/EP0043338B1/de
Expired legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
    • C21C5/28—Manufacture of steel in the converter
    • C21C5/30—Regulating or controlling the blowing
    • C21C5/34—Blowing through the bath
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D1/00—Treatment of fused masses in the ladle or the supply runners before casting
    • B22D1/002—Treatment with gases
    • B22D1/005—Injection assemblies therefor
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/04—Removing impurities by adding a treating agent
    • C21C7/072—Treatment with gases

Definitions

  • the invention relates to refractory, gas-permeable structures for blowing a gas into a metal treatment vessel through its lining.
  • the oxygen-blowing processes used to fresh iron which are known under the names “LD”, “LDAC”, “OLP”, and “BOF” processes, have recently been improved in terms of metallurgy in such a way that secondary gases such as Nitrogen or argon, can be injected in a controlled manner.
  • secondary gases such as Nitrogen or argon
  • the blowing of gas into the metal bath through the vessel bottom or the lining of the vessel walls can also be considered.
  • the gas-permeable refractory bricks to be inserted into the lining of the base or the side walls of the vessel, through which the gas is introduced, are required to have a durability which corresponds to that of the other refractory lining, since a replacement of worn-out gas bubbles in the hot state, for example in the case of a converter base is difficult.
  • the introduction of gas should be possible both continuously and in particular discontinuously; i.e. the vessel should also be able to be operated without introducing gas and, after the gas supply has been switched on again, the stones should be permeable to gas in an unchanged manner.
  • the gas permeability of the stones over their service life, i.e. over an entire kiln trip, remain essentially the same.
  • the previously known gas-permeable stones made of porous refractory material do not meet these requirements. Their shelf life in fresh containers is much lower than that of the surrounding lining material. Porous stones installed in an oxygen converter in the floor can withstand less than 100 batches, while the rest of the lining provides a shelf life of 500 batches and more. Furthermore, a discontinuous gas supply is not possible with porous stones; metal penetrates into the pores of the stones and solidifies there. When the gas supply is switched on again, the stone is no longer sufficiently gas permeable.
  • this refractory, gas-permeable structure consists of at least two segments of refractory, non-porous material lying alongside one another on longitudinal surfaces, and metal layers arranged between them, the segments being combined on the long side by a common metal housing which is sealed on the longitudinal surfaces of the segments, possibly underneath Use of an intermediate mortar layer, and one of the end faces of the structure is provided with at least one connection and a distribution space for the gas supply.
  • a prefabricated block of refractory material has to be cut into the required strips or segments, which is a very complex manufacturing step. Since the segments generally have a small thickness and a large length, segments produced by pressing refractory material are not sufficiently manageable and warp if they are subjected to a stone fire.
  • An object of the invention is to improve the structure of such structures in such a way that simplified production is possible and prefabricated segments with sufficient stability can be used.
  • Another task is to increase the gas throughput capacity without compromising the good durability of the structure.
  • the metal layers are pressed with the refractory material of the segments, at least one of the adjacent longitudinal surfaces of the segments being provided with a metal layer.
  • the structures according to the invention can be designed in such a way that the adjoining longitudinal surfaces of the segments are formed with a smooth or with a profiled, for example corrugated or grooved surface, and also in such a way that the segments with the interposition of metal plates, pairs of metal plates and / or spacers, lie together.
  • the latter can be made from beads or knobs formed in the metal layers, from sheet metal strips, wires or from combustible or vaporizable inserts and the like. consist.
  • a further embodiment can consist in the fact that a second support, For example, a sheet metal plate is attached, for example welded, and that the adjacent longitudinal surface of the neighboring segment is free of metal layers.
  • the profiles can be formed in the longitudinal surfaces of the prefabricated segments made of refractory material by cutting or milling.
  • the segments with co-pressed metal supports with a profiled surface can be produced in a simple manner in that the press ram or the mold wall with the corresponding profiling, e.g. B. corrugation or scoring is provided and an initially flat sheet metal plate and the refractory mass are introduced into the mold. During the pressing process, the profiling is then automatically formed in the pressed sheet metal plate.
  • the press ram or the mold wall with the corresponding profiling e.g. B. corrugation or scoring
  • an initially flat sheet metal plate and the refractory mass are introduced into the mold.
  • the profiling is then automatically formed in the pressed sheet metal plate.
  • the profiled longitudinal surfaces being able to rest against both a smooth and a profiled longitudinal surface of the neighboring segment.
  • the adjacent longitudinal surface of the neighboring segment can in turn be provided with a pressed-on metal support or it can be free of supports.
  • a further embodiment of the structure according to the invention can consist in that at least one co-pressed pair of metal inserts, e.g. Sheet metal, is embedded.
  • Spacers of the type mentioned above can be arranged between the metal plates of a pair of inserts.
  • the extent of the gas permeability can be varied further by the number of insert pairs arranged in a structure and by their configuration with spacers.
  • the structure can be produced in a simple manner by first introducing part of the refractory material into the press mold, then inserting the insert pair, which extends over the entire length of the stone but only over part of the stone width, and finally further refractory Material is filled. If the structure is to have more than one pair of inserts, this process is repeated accordingly. The pressing pressure is then applied perpendicular to the inserts and the structure is thereby shaped. After removal from the press, the inserts on the front of the structure are exposed to allow gas to pass through.
  • a folded sheet or a compressed pipe can also be used. Multi-layer inserts, possibly with spacer elements, are also possible.
  • the extent of the gas permeability can be varied by the number of insert pairs arranged in a structure. Since the refractory material used for the building structure can correspond to that of the rest of the lining, the building structure has the same durability as the lining surrounding it. An early renewal of the gas passage stones is not necessary.
  • the structures can also be operated without gas supply. While some metal penetrates into the narrow gap between the inserts of a couple, when the gas supply line is switched on again, this penetrated metal is flushed out of the structure and the original gas permeability is restored. This remains essentially the same over the entire service life of the structure.
  • the structure 1 shown in Fig. 1 has a e.g. Metal housing 2 constructed from welded plates, which surrounds a total of twelve segments 3, which are arranged in two rows of six pieces each. Each segment 3 has a co-pressed metal support 4 and lies with an unreinforced side surface with the interposition of a mortar layer, not shown, close to the inside of the metal housing 2. This prevents the undesirable, because uncontrollable, gas flow along the metal housing.
  • a sheet metal plate 5 is inserted between the two rows of the segments 3, along which a gas passage can take place, as well as along the metal supports 4 of the segments 3.
  • a pair of plates can also be arranged.
  • the sheet metal plate 5 or the pair of plates can be mortared.
  • the segments 3 are spaced from the end face of the metal housing by means of two strips 6, which are arranged on the inside of the metal housing 2 and are preferably attached to it by spot welding. On this side, which represents the cold side, an end plate 7 is welded tight, which is provided with a pipe connection 8. The one between the front plate te 7 and the end faces of the segments 3 remaining space is the distribution space for the gas.
  • the opposite side of the front side 7, not visible, represents the fire side of the building and can be closed with a cover plate.
  • the latter is used if the infeed of the metal treatment vessel surrounding the structure contains tar or similar carbon carriers. It then serves to prevent the penetration of tar or the like into the gas passage joints of the structure and the sticking of the same during the heating of the vessel.
  • the cover plate melts at the start of operation and releases the joints.
  • a bracket (not shown) can be attached, via which the structure can be hung on a crane hook.
  • segments 30, 31, 32 are shown, which are provided on two, three and four longitudinal surfaces with co-pressed metal supports 4, 41, 42.
  • the latter can be provided with punched claws 9 projecting into the refractory material for better connection to the refractory material.
  • the segment 33 in FIG. 5 has a co-pressed metal support 4 and a second metal support 43 fastened to it by spot welding.
  • the segments 30, 31, 32, 33 can be inserted into the structure according to FIG. 1 instead of the segments 3.
  • the Fig. Shows a segment 34 which is pressed on a longitudinal surface with a profiled and that a corrugated metal pad 44 and on the opposite longitudinal surface with a flat metal pad 4.
  • FIG. 7 shows a segment 35 which can replace three segments 3 of the structure according to FIG. 1.
  • This segment 35 is provided with a U-shaped co-pressed metal support 45 and two pairs of sheet metal inserts 10, which extend over the entire length but only over part of the width of the segment 35.
  • these inserts 10 can be designed as smooth sheet metal strips or, as shown in FIG. 8, as sheet metal strips provided with spacers, such as sikken or grooves 11. To improve the connection between the stone mass and the inserts 10, these can be provided with claws 9.
  • the structure 1 shown in FIG. 9 has a metal housing 2 which surrounds twelve segments which are arranged in two rows of six pieces each. Each segment is provided with a profile on a longitudinal surface, specifically a profile in the form of grooves in the upper segments 34a and one in the form of waves in the lower segments 34. In practice, however, the same type of profiling will be used for all segments.
  • the pressed flat sheet metal plates which are located in the joints between two segments of a row, can also be provided with profiles in one variant.
  • An insert in the form of a pair of sheet metal plates is shown between the two rows.
  • the building body 1 shown in FIG. 10 has a metal housing 2 which surrounds four segments 35. These four segments lie against one another with their U-shaped pressed-in metal supports 45, whereas the unreinforced long sides of the segments lie against the inside of the housing, which e.g. is made from welded plates.
  • Sheet metal is particularly suitable as the material for the metallic inserts, e.g. in a thickness between 0.5 and 3 mm, which can optionally be provided with a surface protection.
  • the structure can, for. B. from a tar-bound magnesia mass with the following composition and the following grain structure:
  • coal tar pitch 4% by weight are added to the sintered magnesia as a binder.
  • Other tars, pitches, synthetic resins or the like also come as binders. into consideration.
  • composition suitable for use in a building structure according to the invention has the following composition and the following grain structure:
  • the components are mixed with 3.7% by weight of kieserite solution with a density of 1.22 g / cm 3 .
  • the invention is not restricted to the use of the refractory materials mentioned.
  • Other refractory materials e.g. B. Mixtures of magnesia and chrome ore, high alumina material can be used.
  • the structures according to the invention have sufficient gas permeability, the passage of gas taking place on the one hand through the joints between the individual segments and on the other hand through the joints between the metal inserts.
  • the segments themselves have practically no gas permeability, and therefore the refractory material used for the structure can correspond to that of the rest of the lining of the metal treatment vessel.
  • the gas-permeable structures have the same durability as that of the lining surrounding them, and premature renewal of the gas-permeable structures is not necessary.
  • a metal plate is generally provided in each joint of the structure through which gas is to pass, whether in the form of metal layers on the segments or in the form of metal plates arranged between the segments. As said, these metal plates or supports prevent the penetration of metal from the metal bath of the treatment vessel into the joints, even in the case of the treatment of pig iron, which due to its consistency and viscosity has a particularly strong tendency to penetrate into the joints.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Mechanical Engineering (AREA)
  • Furnace Housings, Linings, Walls, And Ceilings (AREA)
  • Carbon Steel Or Casting Steel Manufacturing (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
  • Gas Separation By Absorption (AREA)
  • Physical Or Chemical Processes And Apparatus (AREA)
EP81630044A 1980-06-25 1981-06-15 Feuerfeste, gasdurchlässige Baukörper Expired EP0043338B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT81630044T ATE15389T1 (de) 1980-06-25 1981-06-15 Feuerfeste, gasdurchlaessige baukoerper.

Applications Claiming Priority (6)

Application Number Priority Date Filing Date Title
LU82554A LU82554A1 (de) 1980-06-25 1980-06-25 Feuerfester,gasdurchlaessiger baukoerper
LU82552 1980-06-25
LU82553A LU82553A1 (de) 1980-06-25 1980-06-25 Feuerfester,gasdurchlaessiger baukoerper
LU82552A LU82552A1 (de) 1980-06-25 1980-06-25 Feuerfester,gasdurchlaessiger baukoerper
LU82553 1980-06-25
LU82554 1980-06-25

Publications (2)

Publication Number Publication Date
EP0043338A1 EP0043338A1 (de) 1982-01-06
EP0043338B1 true EP0043338B1 (de) 1985-09-04

Family

ID=27350740

Family Applications (1)

Application Number Title Priority Date Filing Date
EP81630044A Expired EP0043338B1 (de) 1980-06-25 1981-06-15 Feuerfeste, gasdurchlässige Baukörper

Country Status (14)

Country Link
US (1) US4395026A (pt)
EP (1) EP0043338B1 (pt)
AU (1) AU539352B2 (pt)
BR (1) BR8103982A (pt)
CA (1) CA1177643A (pt)
CS (1) CS241483B2 (pt)
DD (1) DD159783A5 (pt)
DE (1) DE3172127D1 (pt)
ES (1) ES259132Y (pt)
IN (1) IN155938B (pt)
PL (1) PL132680B1 (pt)
PT (1) PT73175B (pt)
RO (1) RO82232A (pt)
SU (1) SU1255057A3 (pt)

Families Citing this family (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
LU82597A1 (de) * 1980-07-09 1982-02-17 Arbed Feuerfester,gasdurchlaessiger baukoerper
LU83247A1 (de) * 1981-03-23 1983-02-22 Arbed Verfahren und vorrichtung zum behandeln von metallschmelzen im rahmen metallurgischer prozesse
LU83313A1 (de) * 1981-04-22 1983-03-24 Arbed Verfahren und einrichtung zum direkten herstellen von fluessigem eisen
LU83314A1 (de) * 1981-04-24 1983-03-24 Arbed Verfahren und vorrichtung zum entschwefeln von eisenschmelzen
LU83826A1 (de) * 1981-12-09 1983-09-01 Arbed Verfahren und einrichtung zum direkten herstellen von fluessigem eisen
US4462576A (en) * 1982-02-24 1984-07-31 Didier-Werke Ag Apparatus for supplying gas through the wall of a metallurgical container
LU84167A1 (de) * 1982-05-25 1983-11-23 Arbed Feuerfeste,gasdurchlaessige baukoerper
CA1206752A (fr) * 1982-06-18 1986-07-02 Jean Goedert Procede et dispositif pour vidanger des recipients metallurgiques
FR2538410B1 (fr) * 1982-12-24 1988-04-29 Siderurgie Fse Inst Rech Element refractaire porte-tuyere et procede de prevention de l'usure du refractaire faisant application dudit element
LU85131A1 (de) * 1983-12-12 1985-09-12 Arbed Gasdurchlaessiger baukoerper aus feuerfestem material
AT382889B (de) * 1984-03-15 1987-04-27 Voest Alpine Ag Spueleinrichtung fuer ein metallurgisches gefaess
US4754954A (en) * 1986-01-29 1988-07-05 Lazcano Navarro Arturo Refractory device for introducing a gas into a molten metal and a method for making the device
AT384034B (de) * 1986-02-03 1987-09-25 Voest Alpine Ag Spueleinrichtung fuer ein metallurgisches gefaess
CA2091280C (en) * 1991-06-18 1996-06-11 Michael D. Ii Labate Device for directional gas distribution into molten metal
JP3613686B1 (ja) * 2003-07-25 2005-01-26 日本坩堝株式会社 溶湯運搬用取鍋及び溶湯出湯方法

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
LU54172A1 (pt) * 1967-07-26 1969-05-21
DE2205656C3 (de) * 1972-02-07 1976-01-02 Uralskij Nautschno-Issledowatelskij Institut Tschernych Metallow, Swerdlowsk (Sowjetunion) Gießpfanne zum Metalldurchblasen mit Gas
SE392479B (sv) * 1974-03-20 1977-03-28 Asea Ab Forma vid metallurgiska konvertrar och smeltugnar
FR2455008A1 (fr) * 1979-04-25 1980-11-21 Siderurgie Fse Inst Rech Piece refractaire a permeabilite selective et orientee pour l'insufflation d'un fluide
DE8028296U1 (de) * 1980-10-23 1981-05-27 Arbed S.A., Luxembourg Gasdurchlässiger Ausmauerungskörper aus feuerfestem Material

Also Published As

Publication number Publication date
ES259132Y (es) 1984-03-16
AU7216481A (en) 1982-01-07
CS241483B2 (en) 1986-03-13
BR8103982A (pt) 1982-03-09
ES259132U (es) 1983-07-16
CA1177643A (en) 1984-11-13
PT73175B (en) 1982-09-01
IN155938B (pt) 1985-03-23
PL231843A1 (pt) 1982-03-15
AU539352B2 (en) 1984-09-20
SU1255057A3 (ru) 1986-08-30
PL132680B1 (en) 1985-03-30
PT73175A (en) 1981-07-01
EP0043338A1 (de) 1982-01-06
DE3172127D1 (en) 1985-10-10
RO82232B (ro) 1983-07-30
RO82232A (ro) 1983-08-03
CS386581A2 (en) 1985-07-16
US4395026A (en) 1983-07-26
DD159783A5 (de) 1983-04-06

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